JP2018194691A - Barrel, optical apparatus, and method for manufacturing lens barrel - Google Patents

Abstract

To provide a lens barrel with the focus adjusted while suppressing a relative falling of the lens, an optical apparatus, and a method for manufacturing a lens barrel.SOLUTION: The present invention includes: a ground plane; a first holding member for holding a first lens; and a second holding member for holding a second lens, the second holding member being capable of a relative move along the optical axis to the first lens, the first holding member being fixed to the ground plane with an adhesive after at least one of the position of the first lens to the second lens in a direction perpendicular to the optical axis and the position of the ground plane to the second lens in the optical axis is adjusted.SELECTED DRAWING: Figure 11

Description

  The present invention relates to a lens barrel, an optical apparatus, and a method for manufacturing a lens barrel.

  Conventionally, a technique for adjusting a lens in a lens barrel has been proposed. In Patent Document 1, two groups including a first lens fixed to a first lens holder and a second lens fixed to a second lens holder and having a facing surface facing an optical recording medium. A method for adjusting an objective lens for an optical pickup having a lens is disclosed. In Patent Document 1, the first lens holder and the second lens holder are brought into contact with each other on a contact surface substantially perpendicular to the optical axis, and the first lens and the second lens holder are rotated about an axis perpendicular to the contact surface. Adjust the relative tilt between lenses. Further, the eccentricity of the first lens and the second lens is adjusted by translating the second lens holder relative to the first lens holder in the contact surface. In Patent Document 2, a mechanism for adjusting the inclination of the first lens frame that holds the first lens group and a second lens frame that holds the second lens group are provided, and the second lens frame is the second lens group. A lens barrel is disclosed that is movable in the direction of the optical axis and in which the first and second lens frames can abut.

Japanese Patent No. 3462997 JP 2012-145873 A

  In recent years, there has been a problem that it is difficult to suppress the tilting of the lens so that the lens held on the moving ring and the lens fixed on the base holding the moving ring are parallel to each other. In the method of Patent Document 1, tilt adjustment and eccentricity adjustment are possible, but in order to adjust the distance between the two lenses, it is necessary to provide an adjustment mechanism inside the lens barrel, resulting in an increase in the size of the lens barrel. End up. Moreover, since the lens barrel of Patent Document 2 has an inclination adjustment mechanism, the lens barrel is increased in size and weight.

  An object of the present invention is to provide a lens barrel, an optical device, and a method for manufacturing the lens barrel that are adjusted in focus while suppressing relative tilting of the lens.

  A lens barrel according to one aspect of the present invention includes a base plate, a first holding member that holds a first lens, and a second lens, and is arranged along an optical axis with respect to the first lens. A relatively movable second holding member, wherein the first holding member is positioned in a direction perpendicular to the optical axis of the first lens with respect to the second lens, and the first After at least one of the positions of the base plate in the optical axis direction with respect to the second lens is adjusted, the base plate is fixed to the base plate through an adhesive.

  According to another aspect of the present invention, there is provided a method of manufacturing a lens barrel, comprising: a base plate; a first holding member that holds a first lens; and a second lens. And a second holding member that is relatively movable along the optical axis, wherein the second holding member is movable on the base plate so as to be movable along the optical axis. An attaching step; a position in a direction perpendicular to the optical axis of the first lens with respect to the second lens in a state where the first holding member is held by the second lens; and the second lens And adjusting the position of at least one of the positions of the base plate in the optical axis direction, and fixing the first holding member to the base plate with an adhesive.

  According to the present invention, it is possible to provide a lens barrel that is adjusted in focus while suppressing the relative tilting of the lens.

It is the schematic of an imaging device provided with the lens barrel which concerns on embodiment of this invention. It is a disassembled perspective view of a lens barrel. It is sectional drawing of the lens-barrel of a telephoto state. It is sectional drawing of the lens barrel of a wide angle imaging | photography state. It is sectional drawing of the lens-barrel of a retracted state. It is a disassembled perspective view of the focus lens unit when viewed from the subject side. It is a disassembled perspective view of the focus lens unit when viewed from the image plane side. It is a perspective view of a focus lens unit. It is a front view of a focus lens unit. It is a top view of a focus lens unit. It is sectional drawing of the focus lens unit at the time of optical adjustment. It is a rear view of a focus lens unit. It is a figure which shows the state before a focus motor is integrated in a 3 group cylinder. It is a figure which shows the state in which the focus motor was integrated in the 3 group cylinder.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In each figure, the same members are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic diagram of an imaging apparatus IA including a lens barrel LB according to an embodiment of the present invention. The lens barrel LB holds the imaging optical system IOS. The camera body CB holds the image sensor IE. The lens barrel LB may be configured integrally with the camera body CB, or may be configured to be detachably attached to the camera body CB. The lens barrel LB may hold the image sensor IE.

  The present invention is not limited to a lens barrel or a lens-integrated camera that is detachably attached to a camera body, but also a photographing device such as a video camera or a surveillance camera, an observation device such as a binocular, and an image projection device such as a liquid crystal projector. It can also be applied to optical equipment.

  FIG. 2 is an exploded perspective view of the lens barrel LB. FIG. 3 is a cross-sectional view of the lens barrel LB in the telephoto state. FIG. 4 is a cross-sectional view of the lens barrel LB in the wide-angle shooting state. FIG. 5 is a sectional view of the lens barrel LB in the retracted state.

  The lens barrel LB of the present embodiment includes a first lens group 1, a second lens group 2, a third lens group 3, a fourth lens group 4, a fifth lens group 5, an optical filter 6, an image sensor 7, and an aperture unit 8. Each lens group moves from the storage position shown in FIG. 5 to the wide shooting possible position shown in FIG. 4, so that the lens barrel LB becomes ready for shooting. Further, the photographing magnification can be changed by moving each lens group along the optical axis of the imaging optical system between the telephoto-capable position in FIG. 3 and the wide-photographable position in FIG. 4.

  The first group lens holding frame 10 fixes the first group lens 1 with an adhesive. The adhesive is hidden by the decorative board. A follower pin is provided inwardly at the end of the first lens group holding frame 10 on the image plane side.

  The aperture unit 8 holds an aperture mechanism including an aperture blade, a blade drive ring, and an aperture motor. Three apertures projecting toward the image plane side are provided on the image plane side of the aperture unit 8, and a follower pin protruding outward (radially outward) is provided at the tip of each leg.

  The second group lens holding frame 20 holds an optical camera shake correction mechanism that moves the second group lens 2 and the second group lens 2 in a plane orthogonal to the optical axis, and a shutter mechanism. Three legs projecting to the image plane side are provided on the image plane side of the second group lens holding frame 20, and a follower pin protruding to the outer peripheral side (radially outward) is provided at the tip of each leg. .

  The fifth group lens holding frame 50 fixes the fifth group lens 5. Three follower pins protruding outward in the radial direction are provided on the outer periphery of the fifth group lens holding frame 50. The light shielding plate 55 closes the outer side of the fifth group lens holding frame 50 and the inner periphery of the fixed cylinder 72, and three follower pins protruding radially outward are provided on the outer periphery.

  The image sensor 7 is held in the image sensor holding frame 71, photoelectrically converts the subject image formed by the image pickup optical system, and outputs it as an image signal. A fixed cylinder 72 and a cover cylinder 73 are fixed to the image sensor holding frame 71.

  A drive ring 74 is held on the outside of the fixed cylinder 72 so as to be rotatable with respect to the fixed cylinder 72. A gear (not shown) is provided on the outer periphery of the drive ring 74 and is rotationally driven by a zoom motor 79 via a speed reduction mechanism (not shown). A movable cam ring 75 is disposed on the inner periphery of the fixed cylinder 72. Three follower pins (not shown) are equally provided on the outer periphery of the moving cam ring 75, and three drive keys (not shown) are provided equally on 120 °. The follower pin engages with a cam groove 72 </ b> A provided on the inner periphery of the fixed cylinder 72. The drive key is inserted through the through cam groove 72B provided in the fixed cylinder 72 and engaged with a drive groove (not shown) provided along the optical axis on the inner periphery of the drive ring 74. When the drive ring 74 is rotated by the zoom motor 79, rotational torque is transmitted to the moving cam ring 75 via the drive groove, and the moving cam ring 75 moves along the optical axis while rotating according to the locus of the cam groove 72A.

  A cam cover cylinder 78 is disposed between the outer periphery of the moving cam ring 75 and the inner periphery of the fixed cylinder 72. The cam cover cylinder 78 is fixed to the moving cam ring 75 by a snap fit. A rectilinear guide tube 76 is disposed on the inner periphery of the moving cam ring 75. A flange portion is provided along the outer circumferential direction at the subject side end of the rectilinear guide tube 76. The image side surface of the flange portion is in contact with the subject side end surface of the moving cam ring 75. A rectilinear guide plate 77 is fixed to the rectilinear guide tube 76 by a snap fit at an end on the image plane side of the rectilinear guide tube 76. The rectilinear guide plate 77 has a flat plate shape, and the surface on the subject side is in contact with the end surface on the image surface side of the moving cam ring 75.

  A plurality of unillustrated rectilinear keys are provided on the outer periphery of the rectilinear guide plate 77 so as to extend to the outer peripheral side. By engaging with rectilinear grooves 72 </ b> C provided on the inner periphery of the fixed cylinder 72, The rotation of the guide plate 77 is restricted. Therefore, when the drive ring 74 is rotated by the zoom motor 79, the linear guide cylinder 76 and the linear guide plate 77 move along the optical axis together with the moving cam ring 75 without rotating.

  Three cam grooves (not shown) are equally provided on the outer periphery of the movable cam ring 75 at 120 °, and three first cam grooves (not shown) and three second cams are provided on the inner periphery. A groove and three third cam grooves are provided equally at 120 °. The cam groove provided on the outer periphery engages with the follower pin of the first group lens holding frame 10. The first cam groove is engaged with a follower pin of the aperture unit 8, the second cam groove is engaged with a follower pin of the second group lens holding frame 20, and the third cam groove is formed with a follower pin of a third group cylinder 30 described later. Engage.

  A rectilinear key is provided on the outer periphery of the flange portion provided in the rectilinear guide tube 76, and is engaged with the rectilinear groove provided on the inner periphery of the first group lens holding frame 10, thereby holding the first group lens. The rotation of the frame 10 is restricted. In the cylinder main body portion of the rectilinear guide cylinder 76, three first rectilinear through grooves and three second rectilinear through grooves are provided equally at 120 °. The first rectilinear through groove is formed by a wall parallel to a line connecting the optical axis and the center of the first rectilinear through groove, and engages with a rectilinear guide provided at the root portion of the follower pin of the aperture unit 8, The rotation of the aperture unit 8 is restricted. Further, the first rectilinear through groove engages with a rectilinear guide provided at the root portion of the follower pin of the second group lens holding frame 20 to restrict the rotation of the second group lens holding frame 20. The second rectilinear through groove is constituted by a wall parallel to a line connecting the optical axis and the center of the second rectilinear through groove, and is related to the rectilinear guide portion 30B provided at the root portion of the follower pin 30A of the third group cylinder 30. By combining, the rotation of the third group cylinder 30 is regulated.

Three first cam grooves and three second cam grooves are provided on the inner circumference of the drive ring 74 equally at 120 °.
The first cam groove is cam-engaged with the follower pin of the fifth group lens holding frame 50. The second cam groove is cam-engaged with the follower pin of the light shielding plate 55.

  The fixed cylinder 72 is provided with three through straight grooves equally spaced by 120 °. On the inner periphery of the fixed cylinder 72, a fifth group lens holding frame 50 and a light shielding plate 55 are provided. When the rectilinear guide portion at the base of the follower pin provided on the outer periphery of the fifth group lens holding frame 50 is engaged with the through straight groove of the fixed cylinder 72, the rotation of the fifth group lens holding frame 50 is restricted. A follower pin is provided on the outer periphery of the light shielding plate 55, and the rectilinear guide portion at the base of the follower pin is engaged with a rectilinear groove provided in the fixed cylinder 72, whereby the rotation of the light shielding plate 55 is restricted.

  The configuration of the focus lens unit 300 including the third group lens 3 and the fourth group lens 4 will be described below with reference to FIGS. FIG. 6 is an exploded perspective view of the focus lens unit 300 when viewed from the subject side. FIG. 7 is an exploded perspective view of the focus lens unit 300 when viewed from the image plane side. FIG. 8 is a perspective view of the focus lens unit 300. FIG. 9 is a front view of the focus lens unit 300. FIG. 10 is a top view of the focus lens unit 300. FIG. 11 is a cross-sectional view of the focus lens unit 300 during optical adjustment. FIG. 12 is a rear view of the focus lens unit 300.

  The third group lens holder 31 as the first holding member holds the third group lens 3, and the fourth group lens holder 40 holds the fourth group lens 4. The third group lens holder 31 is fixed to the third group cylinder (base plate) 30 via an adhesive 35. The third group cylinder 30 fixes a focus motor 33 that supplies a driving force and a guide shaft 32 that supports the fourth group lens holder 40 so as to be movable along the optical axis. A sheet metal member is integrally attached to the focus motor 33. A flange portion (mechanical stopper) 33A is provided at the tip of the sheet metal member. A screw portion 33C is provided between the flange portion 33A and the focus motor 33. The screw portion 33C is rotated by energization from a circuit (not shown). The guide shaft 32 fits with the sleeve portions 40A and 40B of the fourth group lens holder 40 as a holding member, and guides the fourth group lens holder 40 in a straight line. A rack (contact member) 42 is attached to the fourth group lens holder 40. The rack 42 is screwed into the screw portion 33 </ b> C and is biased in the optical axis direction and the radial direction by the spring 43. The fourth group lens holder 40 moves along the optical axis with respect to the third group cylinder 30 by driving the focus motor 33 during focusing, thereby focusing the subject image on the imaging surface of the image sensor 7.

  On the image plane side of the third group cylinder 30, three legs 30C projecting toward the image plane side are provided. At the tip of the leg 30C, a follower pin 30A protruding to the outer periphery is provided. As described above, the rectilinear guide portion 30B provided at the root portion of the follower pin 30A regulates the rotation of the third group cylinder 30 by inserting the second rectilinear through groove provided in the rectilinear guide tube 76. Yes.

  As described above, in the present embodiment, when the zoom motor 79 is driven, the drive ring 74 rotates, and the moving cam ring 75 moves along the optical axis while rotating. The rectilinear guide plate 77 and the rectilinear guide tube 76 move along the optical axis together with the moving cam ring 75 without rotating. The first group lens holding frame 10, the diaphragm unit 8, the second group lens holding frame 20, the third group cylinder 30, the fifth group lens holding frame 50, and the light shielding plate 55 are not rotated but follow the locus of the respective cam grooves. Move along the optical axis.

  Hereinafter, optical adjustment of the focus lens unit 300 will be described. 6 and 7, first, the third group lens 3 and the fourth group lens 4 are press-fitted and fixed to the third group lens holder 31 and the fourth group lens holder 40, respectively, and then bonded. In addition, you may fix by heat caulking, welding, etc. instead of adhesion | attachment. Next, the guide shaft 32 is pivotally supported by the sleeve portions 40 </ b> A and 40 </ b> B of the fourth group lens holder 40 and simultaneously press-fitted and fixed to the bearing portions 30 </ b> E and 30 </ b> F of the third group cylinder 30. At the same time, the key 40C of the fourth group lens holder 40 is fitted in the groove 30D of the third group cylinder 30. When the key 40C is fitted in the groove 30D, the relative rotation of the third group cylinder 30 and the fourth group lens holder 40 around the guide shaft 32 is restricted.

  Therefore, in FIG. 9, the position of the fourth group lens holder 40 and the third group cylinder 30 is fixed by the guide shaft 32 in the direction parallel to the paper surface, and can move in the direction perpendicular to the paper surface, that is, in the optical axis direction. it can. In the fourth group lens holder 40, the sleeve part 40A of the fourth group lens holder 40 collides with the bearing part 30E of the third group cylinder 30, and the sleeve part 40B of the fourth group lens holder 40 becomes the bearing part 30F of the third group cylinder 30. It is possible to move along the optical axis between the collision state Y.

  After that, as shown in FIG. 11, the flat surface portion 4 </ b> A provided on the subject side of the fourth group lens 4 is brought into contact with the flat surface portion 31 </ b> A provided on the third lens group holder 31. When the flat surface portion 4A and the flat surface portion 31A are brought into contact with each other, specifically, when the fourth lens group 4 holds the third lens group holder 31, the third lens group 3 and the fourth lens group 4 are tilted by these members. It is constant within the range of manufacturing error of the third group lens holder 31 arranged between the two lens groups. In this state, the optical decentration adjustment of the third group lens 3 and the fourth group lens 4 is performed. Further, the position in the optical axis direction with respect to the fourth group lens 4 of the third group cylinder 30 whose position in the direction perpendicular to the optical axis is determined by the guide shaft 32 is adjusted. Adjusting the position of the third group cylinder 30 in the optical axis direction means adjusting the position of the third group lens holder 31 in the optical axis direction when the third group cylinder 30 moves according to the cam locus. Therefore, focus adjustment is performed by this adjustment.

  After the adjustment, the third group lens holder 31 is solidified after filling the areas 35A, 35B, and 35C shown in FIG. 9 with the adhesive 35 in a state where the third group lens holder 31 is not in contact with the third group cylinder 30 (a state where it is floated in the air). Thus, the third group cylinder 30 is fixed. In the present embodiment, as the adhesive 35, an adhesive that is solidified and cured by liquid or gel UV irradiation for fixing two non-contact objects is used.

  After the third group cylinder 30 and the third group lens holder 31 are bonded, the relative positional relationship between them in the optical axis direction is changed so that the fourth group lens 4 and the third group lens holder 31 are not in contact with each other. At this time, the rack 42 and the spring 43 are assembled in the fourth group lens holder 40. Thereafter, as shown in FIG. 13, the focus motor 33 is moved along the direction A while meshing the rack 42 with the screw portion 33 </ b> C, and the key portion 33 </ b> B of the focus motor 33 is sandwiched between the press-fit portions 30 </ b> H of the third group cylinder 30. Press-fit and fix in place. At the same time, the key portion 33B is press-fitted and fixed while being sandwiched between the semicircular portions 30G shown in FIG. FIG. 14 shows a state in which the focus motor 33 is incorporated in the third group cylinder 30.

  Thereafter, the hatched areas 35D and 35E in FIG. 10 are filled with the adhesive 35 and then solidified, whereby the arms 33D and 33E extending from the sheet metal member attached to the focus motor 33 are moved to the third group cylinder 30. Glue together with the dents. By fixing the focus motor 33 by bonding, the screws for fixing the focus motor 33 can be eliminated, so that the deformation of the third group cylinder 30 can be prevented. As a result, the direction of the lens can be prevented from changing due to the deformation of the third group cylinder 30.

  As shown in FIG. 10, the stopper surface 42 </ b> A of the rack 42 contacts the inner periphery of the flange portion 33 </ b> A of the focus motor 33, and the fourth group lens holder 40 is in a state Z that cannot move to the subject side. Therefore, the movement range of the fourth group lens holder 40 in the optical axis direction is restricted from the state Z to the state X, and the fourth group lens 4 does not contact the third group lens holder 31. Therefore, after the assembly, the fourth group lens 4 is not damaged by the collision of parts, and the adjustment is not distorted.

  As described above, the third group lens 3 and the fourth group lens 4 are bonded to the third group cylinder 30 in the air while the fourth group lens 4 and the third group lens holder 31 are in contact with each other. The relative fall of can be suppressed.

  Further, the space between the third group lens holder 31 and the third group cylinder 30 is filled with the adhesive 35 in a state where the third group cylinder 30 is floated, so that the adjustment can be easily performed and an adjustment mechanism needs to be mounted inside. This is advantageous for miniaturization.

  Further, after the adjustment adhesion, the fourth group lens holder 40 can move along the optical axis via the guide shaft 32 in a state where the fourth group lens 4 is prevented from coming into contact with the third group lens holder 31.

  In the present embodiment, the third group lens holder 31 is mounted on the fourth group lens 4 for adjustment, but the present invention is not limited to this. For example, the third group lens 3 may be mounted on the fourth group lens 4 and adjusted without providing the third group lens holder 31.

  In the present embodiment, the fourth group lens 4 is moved along the optical axis by the guide shaft 32. However, as in the other groups, the fourth group lens 4 may be configured to move along the optical axis by the cam groove with a follower pin. Good.

  Further, it is not the fourth group lens 4 that receives the third group lens holder 31 at the time of adjustment, but the fourth group lens holder 40 may lift the third group lens holder 31.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

3 Group 3 lens (first lens)
4 4 lens group (second lens)
30 Group 3 cylinder (base plate)
31 Third lens group holder (first holding member)
35 Adhesive 40 4th lens holder (second holding member)

Claims (8)

With the main plate,
A first holding member for holding the first lens;
A second holding member that holds the second lens and is movable relative to the first lens along the optical axis;
The first holding member has a position in a direction perpendicular to the optical axis of the first lens with respect to the second lens in a state where the second lens holds the first holding member, and A lens barrel, wherein at least one of positions of the base plate in the optical axis direction with respect to the second lens is adjusted, and then fixed to the base plate through an adhesive.   An abutting member attached to the second holding member and further abutting against a mechanical stopper attached to the base plate before the second lens contacts the first holding member. The lens barrel according to Item 1.   The lens barrel according to claim 2, wherein the mechanical stopper and the contact member are attached after the first holding member is fixed to the base plate via the adhesive. A motor for supplying a driving force for driving the second holding member;
The lens barrel according to claim 2, wherein the mechanical stopper is a sheet metal attached to the motor.   The lens barrel according to any one of claims 2 to 4, wherein the mechanical stopper is fixed to the base plate through an adhesive.   The lens barrel according to claim 1, further comprising a guide shaft fixed to the base plate and supporting the second holding member so as to be movable along the optical axis. .   An optical apparatus comprising the lens barrel according to claim 1. A base plate, a first holding member that holds the first lens, a second holding member that holds the second lens and is movable relative to the first lens along the optical axis; A method of manufacturing a lens barrel having
Attaching the second holding member to the base plate movably along the optical axis;
With the first holding member held by the second lens, the position of the first lens relative to the second lens in the direction perpendicular to the optical axis, and the ground plate relative to the second lens Adjusting at least one of the positions in the optical axis direction;
A step of fixing the first holding member to the base plate via an adhesive.